years ago I took an emergency responder type class, and a dude in the class had a story about every type of horrible accident you could ever think of "just one drop of gasoline in a 1 gal can and it blew the frecking garage door off"
Me being the kid that blew **** up and lit stuff on fire, well I still do that, it was really hard for me not to tell him to shut the **** up... but being the weird rednecks from out of town surrounded by soccer moms and computer geeks it probably wouldn't have gone well.
Regardless, folks fill up running motors daily across the world, its hazardous yes, but its doable, is it stupid only if you don't understand the consequences. Would I refill a running airplane, probably not, cause an airplane needs a bunch more then just fuel when it stops, have I refilled a running saw probably, would I do it again probably. Have i poured gas on a roaring fire Hel's yes, would I do it again... um yeah.
Some friends of the family back in WY where stealing gas out of another friends truck, the only truck in town with gas in it at the time (population was in the low 30's, that kind of town) one of the brothers after sucking on ye ole garden hose, decided to light a cigarette, and his face... and hands, the other brother having seen this (he being the one holding the can) threw the can getting himself on fire, and his brother more on fire... also lighting the truck on fire... the only truck in town with fuel in it at the time.
To make a fairly long story a little shorter, they ended up having to wake up the other friend, so that he could drive them the 80 miles to the nearest hospital, no ambulance in this town, Bart spent 6 months in the Gillette burn center, Brian spent about 6 weeks, Piere drove that truck for several more years, it already had brushed on flames, so the soot and what not was just left for effect.